Crossover Design:
As mentioned earlier, Ashley's concern for the difficulty of blending an 8 inch woofer and a 1 inch soft dome tweeter in a high quality two-way design pushed her to a lower than usual high-pass frequency, 2000Hz.  The published Fs for the Dayton #275-070 tweeter is about 900 Hz, so 2000 Hz seemed o.k.  Unfortunately, impedance sweeps of 10 of these tweeters revealed all were 150 to 400 Hz higher at Fs than published.   The best pair (lowest Fs) were selected for Ashley's speakers.  She disdained any of the modifications others (including me) have made to these tweeters in search of lower Fs.  We predicted and then measured some resonance in the tweeter crossed over at 2000 Hz, even third order.  It was decided to incorporate impedance resonance compensation on the tweeters (more commonly done with woofers, I believe).  So, with Zobels on both drivers and with additional filtration on the tweeter and with a 4 dB L-Pad (tweeter) and all within a 3rd order Butterworth network, Ashley constructed the crossover networks depicted in the screen capture below:
Components:

Inductors: L2: 14 gauge air core
         (or 16 gauge air core hand wound)
                L1:  20 gauge bobbin core
                L3:  18 gauge air core
                LM: 18 gauge air core

Capacitors: All non-polar electrolytics
                except film & foil bypasses on
                C1 and C2
                Most capacitances achieved by
                summing smaller values in
                parallel.

Resistors: Sand Cast wire wound
                Non-inductive when in series
                with tweeter (Rp1) and when
                only value available

Connections: Direct lead to lead soldering
                 when possible, 16 guage
                 magnet wire elsewhere.
                 Above board leads are
                 color coded 16 gauge hookup
                 wire.

Topology:   Note that the high and low
                  pass sections are separate
                  so that biamplification and/or
                  biwiring is possible.
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